Iranian Student Builds Blood Artery !!!

[donsaeid]

دانشمند جوان ايراني رگ مصنوعي ساخت


دانشجوي دكتراي دانشكده مهندسي نساجي دانشگاه صنعتي اميركبير نوعي رگ مصنوعي از جنس داكرون را با موفقيت ساخت.



به نقل از روابط عمومي اميركبير، آزيتا آسايش مجري طرح با اشاره به برخي بيماريهاي عروقي مانند گشادشدگي ديواره رگ (آنوريسم) و گرفتگي عروق (آنرواسكلروز) و با توجه به اينكه هميشه امكان جايگزيني عروق طبيعي به جاي عروق آسيب*ديده وجود ندارد، اهميت پيوند رگ*هاي مصنوعي را يادآور شد.

وي افزود: رگ مصنوعي لوله*هايي هستند كه جايگزين بخشي از رگ*هاي طبيعي كه دچار گرفتگي شده يا ديواره آنها ضعيف شده و قادر به انجام وظيفه خود به عنوان مجراي خون نيستند مي*شوند.

مجري طرح گفت: به دليل خواص مكانيكي و شيمايي مناسب و مقاومت در برابر تخريب بيولوژيكي، متداول*ترين مواد مورد استفاده در توليد رگهاي مصنوعي، داكرون (پلي اتيلن ترفتالات) و تفلون (پلي تترافلوئور اتيلن است)
آسايش خاطرنشان كرد: رگهاي مصنوعي با ساختار منسوج (پارچه*اي) با ساختارهاي تاري - پودي، حلقوي تاري و حلقوي پودي توليد مي*شوند.

وي اظهار داشت: در اين طرح با توجه به وارداتي بودن رگهاي مصنوعي مورد نياز جراحان و همچنين نبود ماشين*هاي بافت رگ در كشور، با تغييرات اساسي در ماشين*هاي بافندگي با ماكو و اضافه كردن برخي قطعات، امكان بافت پارچه*هاي ظريف داكروني به گونه*اي فراهم شد كه پارچه لوله*اي بدون درز (دوخت) به قطر متوسط 16 ميليمتر بافته شد.

آسايش تصريح كرد: آزمون*هاي مربوط به خواص مكانيكي نمونه*ها در حال انجام است و انجام كشت سلولي روي نمونه*هاي مذكور و بررسي خواص مكانيكي آنها پس از كشت سلولي در آينده صورت خواهد گرفت.

وي بخش مهم ديگر طرح را آزمون*هاي خستگي ذكر كرد و گفت: رگ*هاي مصنوعي به تدريج و بر اثر فشارهاي متناوب جريان خون خاصيت ارتجاعي خود را از دست مي*دهند كه اين امر مي*تواند منجر به تشكيل لخته، اغتشاش در جريان خون و حتي پارگي محل بخيه رگ مصنوعي شود.

مجري طرح افزود: علت انحصار فناوري توليد رگ مصنوعي در دست كشورهاي سازنده، نه تنها ماشين*هاي بافنده رنگ بلكه دستگاه*هاي آزمون خستگي نيز در اختيار ما قرار داده نشده است.

آسايش در پايان گفت: كه آزمون*هاي خستگي به منظور اطمينان از كاركرد مطلوب رگ مصنوعي در دراز مدت، روي نمونه*هاي مذكور با استفاده از دستگاه*هاي موجود تست خستگي در حال انجام است

[IQ]

damesh garm.

[Khorsheed]

thanks for sharing ..

[donsaeid]

bekhoda yekam arameshe siasi va amniat va azadi dashtim china, india, hatta europe va US ro mizashtim to jibe kochikemon

[mike435]

bekhoda yekam arameshe siasi va amniat va azadi dashtim china, india, hatta europe va US ro mizashtim to jibe kochikemon

ture that
omg first time i am agreeing with you
whats going on

[mike435]

please also post in english barikala mashala

[donsaeid]

please also post in english barikala mashala

please also learn to read persian barikala mashala

[mike435]

please also learn to read persian barikala mashala

lol yea can you give me keywords so i can fined it on the net
i typed Iranian Student Builds Blood Artery nothing came up

[donsaeid]

ill try to find it! i dont have english text but try to go to amir kabir university web page!

[donsaeid]

Arteries are muscular blood vessels that carry blood away from the heart. They are contrasted with veins, which carry blood toward the heart.

The circulatory system is extremely important in sustaining life. Its proper functioning is responsible for the delivery of oxygen and nutrients to all cells, as well as the removal of carbon dioxide and waste products, maintenance of optimum pH, and the mobility of the elements, proteins and cells of the immune system. In developed countries, the two leading causes of death, myocardial infarction and stroke each may directly result from an arterial system that has been slowly and progressively compromised by years of deterioration. (See atherosclerosis).


Description

The arterial system is the higher-pressure portion of the circulatory system. Arterial pressure varies between the peak pressure during heart contraction, called the systolic pressure, and the minimum, or diastolic pressure between contractions, when the heart rests between cycles. This pressure variation within the artery produces the pulse which is observable in any artery, and reflects heart activity.


Anatomy

The outermost layer is known as the tunica adventitia or the adventitia, and is composed of connective tissue. Inside this layer is the tunica media, or media, which is made up of smooth muscle cells and elastic tissue. The innermost layer, which is in direct contact with the flow of blood is the tunica intima, commonly called the intima. This layer is made up of mainly endothelial cells. The hollow internal cavity in which the blood flows is called the lumen.


Types of arteries

There are several types of arteries in the body:


Pulmonary arteries

The pulmonary arteries carry deoxygenated blood that has just returned from the body to the lungs, where carbon dioxide is exchanged for oxygen.


Systemic arteries

Systemic arteries deliver blood to the arterioles, and then to the capillaries, where nutrients and gases are exchanged.


The Aorta

The aorta is the root systemic artery. It receives blood directly from the left ventricle of the heart via the aortic valve. As the aorta branches, and these arteries branch in turn, they become successively smaller in diameter, down to the arteriole. The arterioles supply capillaries which in turn empty into venules.


Arterioles

Arterioles, the smallest of the true arteries, help regulate blood pressure and deliver blood to capillaries.


Arterioles and blood pressure

Arterioles have the greatest collective influence on both local blood flow and on overall blood pressure. They are the primary "adjustable nozzles" in the blood system, across which the greatest pressure drop occurs. The combination of heart output (cardiac output) and total peripheral resistance, which refers to the collective resistance of all of the body's arterioles, are the principal determinants of arterial blood pressure at any given moment.


Capillaries

Though not considered true arteries, the capillaries are where all of the important action happens in the circulatory system:


Functions of capillaries

Capillaries have no smooth muscle surrounding them and have a diameter less than that of a red blood cells; a red blood cell is typically 7 micrometers outside diameter, capillaries typically 5 micrometers inside diameter. The red blood cells must distort in order to pass through the capillaries.

This small diameter of the capillaries provide a relatively large surface area for the exchange of gases and nutrients.


What capillaries do:

* In the lungs, carbon dioxide is exchanged for oxygen
* In the tissues, oxygen and carbon dioxide and nutrients and wastes are exchanged
* In the kidneys, wastes are released to be eliminated from the body
* In the intestine, nutrients are picked up, and wastes released

[Parinaz_M]

afarin, vaghean ke iraniha adamaye ba estedadi hastan
khoda hamamoono negah dare

[Sepideh_UK]

loool
vaagheanaa

EYval....

[honia2002]

Dame shoma garm!

[donsaeid]

Iran Sarvare Hame

[donsaeid]